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Dam Safety Planning Division

Hazard Mitigation

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On June 27, 2017, Governor Brown signed SB 92 into law, which set forth new requirements focused on dam safety. As part of this legislation, dam owners must now submit inundation maps to DWR. After the maps are approved, the dam owner must submit an emergency action plan to Cal OES. The owner must submit updated plans and inundation maps every 10 years, or sooner under certain conditions. Cal OES will review and approve the emergency action plans. This legislation set forth additional provisions for emergency action plans including compliance requirements, exercises of the plan, and coordination with local public safety agencies.

​For Dam Owners:

Cal OES has developed two products to assist dam owners in developing EAPs.

The first is the Blank Formatting Template that dam owners may use to help build their EAPs in a structure that includes required components.

The second is the Cal OES EAP Review Tool that Cal OES uses to ensure that each EAP has the required elements. This product is based on the legislative requirements in California Water Code Sections 6160 and 6161 and Government Code Section 8589.5, which includes FEMA’s Federal Guidelines for Dam Safety: Emergency Action Planning for Dams. All of the elements listed in the Review Tool must be met prior to EAP approval.

Inundation Mapping Information

For information on dam inundation mapping, please refer to the DSOD website.

​For Dam Stakeholders:

Message from the Division of Dam Safety, Department of Water Resources (June 2018)

The Division of Safety of Dams (DSOD) has been developing regulations for inundation maps. Emergency regulations are currently in effect, and we are concurrently working on permanent regulations. We listened to your feedback over the last several months and made changes to improve the proposed permanent regulations.

Attached is the Notice of Proposed Rulemaking that formally initiates the 45-day comment period for the proposed permanent regulations. It contains important details about how to access the documents and submit comments. The Notice is also posted on our website and the OAL Notice Register.

Since many dam owners are currently in the process of preparing maps, DSOD is taking the following steps: 1) Proposed permanent regulations allow DSOD to approve maps that demonstrate substantial compliance – this means that maps prepared under the emergency regulations should be acceptable. 2) Proposed permanent regulations are less prescriptive than the emergency regulations. 3) Emergency regulations will be readopted when they expire next month (7/18/18) with some revisions.

If you have any questions about inundation map requirements or the rulemaking process, please contact Kristen Martin at mapregs@water.ca.gov or (916) 227-2170.

Message from the Division of Dam Safety, Department of Water Resources (November 2017)

Senate Bill 92 added Sections 6160 and 6161 to the Water Code that became effective on June 27, 2017, requiring owners of State regulated dams, except those classified as low hazard, to prepare emergency action plans (EAPs) containing inundation map(s) for emergency preparedness. On October 19, 2017, emergency regulations were adopted to provide standards for preparing and submitting maps to the Division of Safety of Dams (DSOD) for their review and approval. These regulations are available here.

Dam owners must submit EAPs to the Governor’s Office of Emergency Services (Cal OES) for approval by deadlines that are based on the dam’s downstream hazard classification. Dam owners received letters in July identifying their dam’s hazard classification and the statutory deadlines for EAPs as shown below:

It is important to note that inundation maps must first be submitted to DSOD for review and approval, and only approved inundation maps should be contained within EAPs that are submitted to Cal OES for their approval.

Upon approval of the EAP by Cal OES, dam owners are responsible for ensuring that the approved EAP is disseminated to appropriate public safety and emergency management agencies, which includes DSOD. Thank you for your cooperation.

If you have any questions or need additional information, please contact DSOD at MapRegs@water.ca.gov.

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Are there any other statutory requirements for jurisdictional dam owners?

<p>​Yes. At least once annually, the dam owner shall conduct an EAP notification or tabletop exercise with local public safety agencies.<br> <br>Please see the <a title="This is a link to the Division of Safety of Dams webpage" href="https://www.water.ca.gov/Programs/All-Programs/Division-of-Safety-of-Dams" target="_blank">DSOD webpage</a> for statutory requirements related to inundation mapping.</p>

How often is a dam owner required to maintain, update, and revise an EAP?

<p>​Dam owners shall update their EAP, including inundation map(s), at least every ten (10) years. Updates are also required when there is:<br>· a significant modification to the dam or a critical appurtenant structure, as determined by DSOD;<br>· a significant change to downstream development that involves people and property.</p>

<p>​California statute requires that EAPs be developed in accordance with FEMA’s Federal Guidelines for Dam Safety: Emergency Action Planning for Dams. Government Code Section 8589.5 also requires that the EAP must include at a minimum:<br>· Notification flowcharts and contact information<br>· The response process<br>· The roles and responsibilities of the dam owner and impacted jurisdictions following an incident involving the dam<br>· Preparedness activities and exercise schedules<br>· Inundation maps approved by DWR<br>· Any additional information that may impact life or property<br> <br>As needed, Cal OES will develop additional tools and information to aid in the EAP process. <br> <br>California law also requires that EAPs be developed in consultation with any local public safety agency that may be impacted by an incident involving the dam, to the extent a local agency wishes to consult. This process/outreach needs to be documented within the EAP.</p>

I currently have an EAP. Can that be re-submitted for approval under the new requirements?

<p>​If a dam owner has an existing EAP as of March 1, 2017, the owner can submit the inundation map within that plan to DSOD for approval. DSOD will review and may approve the inundation map if it is deemed sufficient. If DSOD approves the map, the dam owner may submit the EAP to Cal OES for review. </p>

<p>​The downstream hazard classifications are based solely on potential downstream impacts to life and property should the dam fail when operating with a full reservoir. These classifications are not related to the condition of the dam or its appurtenant structures. The definitions for downstream hazard classifications are based on the Federal Guidelines for Inundation Mapping of Flood Risks Associated with Dam Incidents and Failures (FEMA P-946, July 2013). FEMA categorizes the downstream hazard potential into three categories in increasing severity: Low, Significant, and High. DSOD adds a fourth category of “Extremely High” to identify dams that may impact highly populated areas or critical infrastructure, or have short evacuation warning times.</p>

<p>​An EAP is a written document that identifies potential emergency conditions at a dam and specifies preplanned actions to help minimize property damage and loss of life should those conditions occur.<br> <br>EAPs contain procedures and information that instruct dam owners to issue early warning and notification messages to downstream emergency management authorities. The document must also contain inundation map(s) demonstrating critical areas for evacuation-related actions. Additionally, EAPs:<br> <br>· Provide assistance and guidance to local jurisdictions on their emergency planning for dam failure events; and<br>· Aid local, state, and federal agencies with activities to ensure effective dam incident emergency response procedures and planning. </p>

<p>​The 60 day review period begins when the Cal OES Dam Safety Planning Division receives the EAP with the approved inundation map included. If an EAP is submitted to<br> Cal OES without an approved inundation map, the review period will begin when the Dam Safety Planning Division receives the letter from DSOD that the applicable inundation map has been approved. </p>

<p>​Deadlines for dam EAP submissions are:<br>· On or before January 1, 2018, if the hazard classification is extremely high.<br>· On or before January 1, 2019, if the hazard classification is high.<br>· On or before January 1, 2021, if the hazard classification is significant.</p>

<p>​Per legislation, the development of an EAP should be based on and include an inundation map approved by DSOD. After development, dam owners must submit the EAP to both Cal OES and DSOD. Please submit the Cal OES copy of the EAP to the Dam Safety Division, to:<br> <br>Jose Lara, Chief<br>Dam Safety Planning Division<br>3650 Schriever Avenue<br>Mather, CA 95655<br> <br>At this time, Cal OES requests that dam owners submit one paper copy of the EAP and one digital copy (email, cd, or thumb drive).</p>

<p>​Sections 6160 and 6161 of the California Water Code and Government Code Section 8589.5 require owners of state regulated dams to submit EAPs to Cal OES and the Department of Water Resources (DWR) Division of Safety of Dams (DSOD), unless the dam has been classified as low hazard by DSOD.</p>

​Owner Education Workshop: Inundation Maps and EAPs

Cal OES and DSOD hosted an Owner Education Workshop on January 30, 2018 to discuss new requirements for inundation maps and EAPs. The Workshop recording is below:

2016 Oroville Dam Inundation Map

Most dam owners are required to prepare inundation maps as part of the dam permitting process. These maps are prepared by civil engineers on behalf of dam owners, as required under California law. Inundation maps are developed from the best available information using reasonable assumptions and standardized methods. The maps are an approximation of the maximum water flow resulting from a complete dam failure. The maps portray a catastrophic failure of the dam, as opposed to the failure a critical appurtenant structure, such as a spillway. This map represents a worst-case scenario contemplating a complete failure of the Oroville Dam. Depending upon actual circumstances, appropriate alert and evacuation areas could be more or less extensive than the simulated zones shown on the maps.